Dyestuffs and process of making same



Patented Apr. 26, 1927.

UNITED STATES PATENT OFFICE.

FRITZ S'IBAUB, OF BASED, SWITZERLAND. ASSIGNOB TO THE FIRM: SOCIETY OF CHEMICAL INDUSTRY IN BASLE, OF BASEL, SWITZERLAND.

DYES'IUFFS AND PROCESS OF MAKING SAME.

No Drawing. Application filed January 29, 1926, Serial No. 84,756, and in Switzerland February 16, 1925.

The present invention relates to new acid dyestuffs containing chromium, valuable for the production of fast shades on the ammal fibre. It comprises the new products, the

process of making same, and the material dyed with the new dyestuffs.

It has been found that valuable new acid wool dyestuffs containing chromium may be obtained by treating the azo dyestulf from diazotized 6-nitro-2-amino-l-phenollsulfonic acid and fl-naphthol corresponding with the following formula:

(1)11 011 N oragNzNg with agents yielding chromium, such as the derivatives of the trivalent chromium.

There are thus obtained new dyestuffs which have to be considered as complex chromium compounds of the azo dyestuffs corresponding with the formula on I on I NO=QN=N and which form black powders dissolving in water with red-violet-black, in dilute caustic soda solution with violet-black coloration dyeing wool from an acid bath reddish-black shades with excellent properties of fastness.

Example.

treating the azo dyestuif from diazotized 6-nitro-2-amino-l-phenoll-sulfonic acid and ,l'E-naphthol with derivatives of the trivalent chromium.

2. A process for the manufacture of new acid wool dyestuffs containing chromium by treating the azo dyestufi' from diazotized 6- nitro-Q-amino-1-phenoll-sulfonic acid and ,B-naphthol with the salts of the trivalent chromium.

3. A process for the manufacture of new acid. wool dyestuffs containing chromium by treating the azo dyestufl' from diazotized 6-nitro 2-amino-1-phenol-4-sulfonic acid and fl-naphthol with chromium fluoride.

4:. As new products the herein described acid wool dyestuffs containing chromium which have to be considered as complex chromium compounds of the azo dyestufls corresponding with the formula OH OH which products form black powders dissolving in water with red-violet-black in dilute caustic soda solution with violet-black coloration, dyeing wool from an acid bath reddish-black shades with excellent properties of fastness.

5. Material dyed with the dyestuffs of claim 4:.

' In witness whereof I have hereunto signed my name this 16th day of January 1926.

FRITZ STRAUB. 

